Over here in the UK, the Austin-Healy Frogeye sprite evolved in to the MG Midget. A friend of mine restored one. They offered the 1600 Triumph engine from the Spitfire after BMC and Triumph merged, to replace the A-series, which was only available up to 1275. the irony is, the 1375 could be tuned to put out more than the relatively untunable Triumph.